Poor conduct by Sequre Trellis

I order a sliding security Gate and Burglar guards from this company. On the day of the installation the Installers knocked down the Exit Gooseneck at the complex. Pictures were taken and submitted to Sequre Trellis. When the installers were asked if we needed to remove the curtains they said it was not necessary as they will move it when required. After the Installation it was found that they damaged one of the curtains. A Drill bit was left stuck in it and two large holes which looked liked it was burnt. I submitted pictures as well. Subsequently the Installers denied any wrong doing and the company refused to pay fo any of the damages. This company Installed gates in my previous house and I have been singing their praise since but not anymore. The Installers blatantly **** about everything.